The antidote that Rosalee made for Nick gets administered in this week's episode of Grimm, "PTZD," and comes with a side effect, while Nick tries to piece together everything that happened with he was a zombie -- and he doesn't like what he hears.

After his bar fight from the last episode, Nick is now going after an innocent family after he barges into their home. Monroe and Hank eventually find him, but thankfully they get there in time before Zombie Nick can do real harm.

They fight him -- hard. Eventually Renard, Juliette and Rosealee catch up to him with the antidote. More fighting ensues -- he even gets Juliette, but she's a good sport about it, not like a "My boyfriend just hit me" kind of reaction. Rosealee stabs Nick with the antidote, but it doesn't work right away, he must be taken to the shop for more because he's cold, shaking and isn't looking any better.

Keeping Quiet

At the shop, Nick is given another dosage and eventually wakens. He's not all there, understandably. He's sweet, concerned Nick again, wondering whether the others were in an accident, rather than asking about him. They try to help him piece what happened together.

Meanwhile, it turns out Renard's half-brother, Eric, has died in a fiery crash. You can imagine how much he's grieving -- none. Renard also gets the news that the man from the bar fight that Nick beat up has died. You think he's at a crossroads at this moment, what to do about Nick, whether to turn him in or protect him. But it seems he made the decision when he was at the scene by destroying the security tapes. But he has a copy of it on his hard drive.

They all agree that Nick is not to be told of what happened, and they'll shift blame to the fake identity Eric had created for Nick.

Not Quite Back to Normal

Nick's antidote doesn't come without some side effects. In bed, Juliette sees the zombie version of Nick again, cold, not responding and without a pulse. But when he eventually awakes, he's completely normal, alert and with the color back in his face.

Something similar happens again when Juliette is being questioned by the police about the bar fight. He's standing in the kitchen with coffee, and you can tell he's disoriented, and then his hand just breaks the mug for no reason.

The Truth

Since Nick was at home when the officers dropped by his place to talk to Juliette, he now knows that he killed someone. He wants to turn himself in -- and he isn't happy everyone around him was lying to him.

They all try to tell him that he wasn't Nick, that he was a deranged version of himself and that he didn't even know what he was doing. The real Nick wouldn't hurt his friends, especially his girlfriend. Renard ends up showing him the tape of what happened, and says that if he did turn himself in, those who want to destroy Grimms would win.

So Nick stays quiet. But for how long? And will what he did change him? Will he be able to forgive those around him for letting him get away with murder?